A Case of Post-Essential Thrombocythemia Myelofibrosis with Severe Osteosclerosis / 대한진단검사의학회지

Essential thrombocythemia (ET) is a chronic myeloproliferative neoplasm that involves primarily the megakaryocytic lineage. After many years, a few patients with ET may develop bone marrow (BM) fibrosis and rarely develop osteosclerosis. A 60-yr-old female was admitted due to severe left upper quadrant abdominal discomfort. She had been diagnosed as ET 19 yrs ago. On liver computed tomography severe splenomegaly was shown. Laboratory tests revealed WBC 24.3x10(9)/L, hemoglobin 13.4 g/dL, platelets 432x10(9)/L, lactate dehydrogenase 4,065 IU/L (reference range; 240-480). Blood smear demonstrated leukoerythroblastosis, teardrop cells, and giant and hypogranular platelets. BM study revealed inadequate aspirate due to dry tap. BM biopsy showed clusters of dysplastic megakaryocytes, grade 3 fibrosis, and severe osteosclerosis. Major/minor BCR-ABL1 rearrangement and JAK2 V617F mutation were not detected. Cytogenetic studies revealed normal karyotype. According to the 2008 WHO diagnostic criteria, the patient was diagnosed as having post-essential thrombocythemia myelofibrosis with severe osteosclerosis.

Evaluation of the BD Phoenix Automated Microbiology System SMIC/ID-2 Panel for Antimicrobial Susceptibility Testing of Streptococcus pneumoniae / 대한진단검사의학회지

BACKGROUND: With the emergence of antimicrobial resistance among Streptococcus pneumoniae, a more accurate and automated antimicrobial susceptibility testing method is essential. We evaluated the BD Phoenix Automated Microbiology System (Becton Dickinson Diagnostic Systems, USA) SMIC/ID-2 panel for antimicrobial susceptibility testing of S. pneumoniae. METHODS: A total of 113 clinical strains of S. pneumoniae (88 penicillin susceptible strains, 8 intermediate strains, and 17 resistant strains by 2008 CLSI criteria) were tested. Minimum inhibitory concentrations (MICs) for penicillin, cefotaxime, clindamycin, erythromycin, levofloxacin, trimethoprim/ sulfamethoxazole, tetracycline, and vancomycin were determined by Etest (AB Biodisk, Sweden) and Phoenix System. The results obtained by Phoenix system were compared to those obtained by Etest. RESULTS: The overall essential agreement of MICs (within one dilution of MICs) defined by the Phoenix and Etest was 92.3%. Neither very major errors nor major errors were produced, and minor errors were 6.5%. Minor errors were frequently observed in susceptibility testings for penicillin (22.1%), cefotaxime (12.4%), and trimethoprim/sulfamethoxazole (11.5%). CONCLUSIONS: The Phoenix SMIC/ID-2 panel provided a simple and rapid susceptibility testing for S. pneumoniae, and the results were in a good agreement with those of Etest. The Phoenix system appears to be an effective automated system in clinical microbiology laboratories.

Evaluation of the Phoenix Automated Microbiology System for Detecting Extended-Spectrum beta-Lactamase in Escherichia coli, Klebsiella species and Proteus mirabilis / 대한진단검사의학회지

BACKGROUND: The aim of this study was to compare the BD Phoenix (Beckton Dickinson Diagnostic Systems, USA) extended-spectrum beta-lactamase (ESBL) test with the Clinical and Laboratory Standards Institute (CLSI) ESBL phenotypic confirmatory test by disk diffusion (CLSI ESBL test) in Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and Proteus mirabilis. METHODS: We tested 224 clinical isolates of E. coli, K. pneumoniae, K. oxytoca and P. mirabilis during May 2006 to March 2007. These isolates were examined by the Phoenix and the CLSI ESBL tests simultaneously. For the isolates showing discordant results between the two tests, boronic acid disk test was performed to differentiate AmpC beta-lactamase and ESBL. RESULTS: Among the 224 clinical isolates, 75 and 79 isolates were positive for ESBL by CLSI ESBL test and Phoenix test, respectively. Having detected 4 more isolates as ESBL-producers, Phoenix test showed a 98.2% agreement with a 100% sensitivity and 97.3% specificity compared with CLSI ESBL test. Among the four false positive isolates, three were AmpC-positive but ESBL-negative. CONCLUSIONS: The BD Phoenix ESBL test was sensitive and specific, and can be used as a rapid and reliable method to detect ESBL production in E. coli, Klebsiella species, and P. mirabilis.

Analysis of Positive Results in Mediace Rapid Plasma Reagin and Treponema pallidum Latex Agglutination as the Automated Syphilis Test / 대한진단검사의학회지

BACKGROUND: We compared the results of automated and quantitative methods for the diagnosis of syphilis, Mediace Rapid Plasma Reagin (RPR) and Mediace Treponema pallidum Latex Agglutination (TPLA) (Sekisui Chemical Co., Ltd, Japan) with those of conventional methods. METHODS: Sera from 3,896 persons who had health checkups between December 2005 and November 2006 were included in the evaluation of positive rates and biological false positives (BFP) for Mediace RPR and TPLA. In addition, 134 patients' sera positive for automated Mediace RPR or TPLA were tested for VDRL and TPHA. Discrepancies between TPLA and TPHA results were confirmed by the RecomBlot Treponemal IgG/IgM (Mikrogen GmbH, Germany). Automated Mediace RPR and TPLA were performed using the Hitachi 7600 chemistry autoanalyzer (Hitachi, Japan). Samples with positive Mediace RPR and negative TPLA results were defined as BFP. RESULTS: Positive rate of automated Mediace RPR was 0.23% (9/3,896). BFP of the Mediace RPR was 0.18%. Positive rate of automated TPLA was 1.62% (37/2,284). Among the 134 patients' sera, 33 (24.6%) showed a discrepancy between conventional VDRL and automated Mediace RPR results: Among 31 Mediace RPR(+)/VDRL(-) sera, 13 were positive and 18 were negative for TPLA. The remaining 2 sera of discrepancy with Mediace RPR(-)/VDRL(+) were all positive for TPLA. There were seven sera that showed a discrepancy between automated TPLA and TPHA results: Two sera with Mediace RPR(+)/TPLA(-)/TPHA(+) showed negative recomBlot Treponemal IgG/IgM results, and among five sera with TPLA(+)/TPHA(-), three demonstrated IgG or IgM by recomBlot Treponemal IgG/IgM. CONCLUSIONS: The results of comparison data demonstrated that automated TPLA results had a high concordance with recomBlot Treponemal IgG/IgM results. Moreover, there are additional advantages of automated methods such as quantitative detection, low infection risk, and no influence by human handling.